Unify Signals/Channels around auto-naming, plot-by-channel, and shared vars

Devices: auto-name from OS-reported port description (Device Manager /
udev string) instead of a generic label; default Serial #Channels 1;
consistent simulate-mode checkbox across backends; inline device rename.

Channels: calibration/filters move out of Signals into a Channel
"Operation" (adds Scale/Offset alongside the existing math kinds);
single-physical-source Channels get an embedded Filters block; new
Channels auto-name/auto-ID from their source and reject duplicate
names/IDs on apply; "Create Channel" button on each Signal row; renamed
"Sources" -> "Signals" in the Channels UI; Signals' READ/WRITE dir badge
(was silently-broken IN/OUT) now reflects the real writable flag.

Plot: default layout is one pane per Channel (not per device, not raw
Signals) titled by channel name; "+ Add Channel" is a checkbox dialog
instead of an inline dropdown; traces get up/down reorder; live unit
changes (e.g. a Mark-10 gauge switching lb/kgF/N/ozF) propagate to an
open pane's axis label without clobbering a manually-typed one.

Control Panel: hardware assignment now picks from the same writable-
Signals list instead of a separate device/channel combo with a
hardcoded Arduino pin list; stale visual indicator when a control's
target device/channel disconnects or disappears; documented the `vars`
bridge (Control Panel On Action Script <-> Channel scripts) in both
directions' help text and script templates.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

1 files changed, 13 insertions, 5 deletions

diff --git a/ui/add_device_dialog.py b/ui/add_device_dialog.py
index 2bf0233..719c5a2 100644
--- a/ui/add_device_dialog.py
+++ b/ui/add_device_dialog.py
@@ -152,13 +152,20 @@ class _DeviceListScanner(QWidget):
 class SerialPanel(QWidget):
     def __init__(self):
         super().__init__()
-        lay = QVBoxLayout(self)
+        lay = QFormLayout(self)
         lay.setContentsMargins(0, 4, 0, 4)
-        note = QLabel("Additional protocol settings available in the device config dialog.")
+
+        self.ch_spin = QSpinBox()
+        self.ch_spin.setRange(1, 32)
+        self.ch_spin.setValue(1)
+        lay.addRow("#Channels:", self.ch_spin)
+
+        note = QLabel("Applies to Key:Value / CSV / JSON formats. "
+                       "SCPI / Modbus / Mark-10 / CML define channels via their own protocol tables "
+                       "(available in the device config dialog after adding).")
         note.setObjectName("traceSource")
         note.setWordWrap(True)
-        lay.addWidget(note)
-        lay.addStretch()
+        lay.addRow(note)
 
 
 class ArduinoPanel(QWidget):
@@ -302,7 +309,7 @@ class AddDeviceDialog(QDialog):
         cfg_form.addRow("Device ID:", self._id_edit)
 
         self._name_edit = QLineEdit()
-        self._name_edit.setPlaceholderText("Leave blank to use the default type name")
+        self._name_edit.setPlaceholderText("Leave blank to auto-name from device + port")
         cfg_form.addRow("Display Name:", self._name_edit)
 
         self._fmt_cb = QComboBox()
@@ -429,6 +436,7 @@ class AddDeviceDialog(QDialog):
                 dev = SerialDevice(
                     device_id=dev_id, port=port, baud_rate=baud,
                     parse_format=fmt, simulate=sim,
+                    num_channels=panel.ch_spin.value(),
                 )
             elif type_name == "Arduino":
                 from devices.arduino_device import _parse_pin_edit, _parse_analog_pin_edit